Manufacture of chilled castings.



PATENTED FEB. 7, 1905.

J. S. SEAMAN.

MANUFACTURE OF GHILLED GASTINGS.

APPLICATION TILED HAY 23. 1904.

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Patented February '7, 190 5.

IJNTTED STATES PATENT Trice.

JOSEPH S. SEAMAN, OF PITTSBURG, PENNSYLVANIA.

MANUFACTURE OF CHILLED CASTINGS.

SPECIFICATION forming part of Letters Patent No. 781,914, dated February7, 1905.

Application filed May 23, 1904. Serial No. 209,310-

To (all whom it In/(1ycon/c772,.-

Be it known that LJosnrir S. SEAMAN, a citizen ofthe UnitedStates,residing at Pittsburg, in the county of Allegheny and State ofPennsylvania, have invented or discovered certain new and usefulImprovements in the Mannfacture of Chilled Castings, of which improvement the following is a specification.

As is well known by those skilled in the art, not only the depth, butalso the hardness of the chill on a roll or other article, depends uponthe rapidity with which heat is carried away from the molten metal andthe etiicient persistence of this cooling action. The contraction of themolten metal during cooling and solidification and the expansion of thechill-ring when heated produce such a separation of the chill-ring andthe cast metal that the former will not act by conduction to cool thecast metal, and the heat retained in the casting by reason of theheating of the chillring and its failure to carry away the heat willproduce an annealing or softening etlcct on the chill produced by thefirst contact of the molten metal with the ring.

The present invention has for its object the employment of a chill-ringwhich will act effectively during the initial cooling of the metal, atwhich time the contraction is greatest, and the substitution of a secondand preferably slightly smaller chill-ring for the first, whereby thearticle will be subjected to a secondary chilling act-ion, which will bemore continuing than the first chilling, and all annealing or softeningaction avoided.

The invention is hereinafter more fully described and claimed.

In the accompanying drawings, forming a part of thisspecification,Figure 1 isa sectional elevation of a mold for castingrolls, a casting being shown in position in the mold; and Fig. is asimilar view showing the parts after the first chill-ring has beenremoved and another ring placed in position.

In the practice of my invention the mold v as regards the drag '1,ch1ll-r1ng2, and runnor 3 are constructed in the usual or any suitablemanner. The cope st may be constructed as is common in the art to permitthe chill-ring being drawn up outside of it, or, and as is preferable,the cope is made in two vertical sections separated from each other by athin metal ring 5. The matrices for the rollneck wabbler and sinker-headare formed of clay within the ring 5, which has an external diameterless than the internal diameter of the chill-ring 2. The space betweenthe ring 5 and the cope-frame at is filled witha material such as sand,which will not cake or harden when heated.

After the mold has been formed in the manner stated the metal is teemedin through the sprue, as is customary. The molten metal on coming intocontact with the (jllill'l'ilig' is cooled and hardened. As the heat isconducted away from the metal by the chill-ring the latter will expandby reason of the heat absorbed,aml the casting will contract. Theseopposite movements will so separate the casting and the chill-ring, thatthe latter will no longer act with the desired cflicieucy. This loss ofeliiciency is due not only to the separation of the casting andchill-ring. but also to the heating of the chill-ring by the moltenmetal, so that the chill formed by the first contact of the molten metalwith the chill-ring will be softened by the annealing of the retainedheat. As soon as this separation of the casting and the chillring hastaken place and the shell of solidified metal forming the exterior ofthe casting has becomesuilicicntly rigid to prevent dcformation of thecasting when the chillring is removed the cope-frame and the materialbctween it and the ringo are removed and the chill-ringZ stripped otithe casting. A second ehillring 2, preferably of slightly less diameterthan the ring 2, is slipped down onto the casting. As this ring is coldand will come into direct contact with the surface of the casting, asecond chilling action will occur and will continue for a longer time,as the contraction of the casting at this stage is not as rapid as atfirst, nor will the chill-ring 2 be heated and expanded as rapidly.

1 claim herein as my invention 1. As an improvement in the art ofmanufacturing chilled castings the method herein described whichconsists in casting the metal against a chill, removing the latter andsubremoving the chill-ring and substituting an-,

stituting' a second chill therefor, substantially as set forth.

2. As an improvement in the art of manufacturing chilled rolls, themethod herein described Which consists in casting the molten metal incontact with a chill-ring, permitting the formation of a rigid shell onthe casting,

other therefor, substantially as setforth. IO

In testimony whereof I. have hereunto set my hand.

JOSEPH S. SEAMAN. Witnesses:

DARWIN S. WOLCOTT, F. E. GAITHER.

